Trucks were being sorted into two lines, one with more rigorous screening. Agents used a variety of devices to check the exteriors of the trailers, including a large drive-through machine similar to a security tool used at the Super Bowl, and a tool that measures radiation.
Remember when everyone said that the episode of 24 where the Muslim terrorists set off a nuke in Los Angeles was "jumping the shark"? Afraid not. I'm glad that I don't live in any large cities.